Years ago, I got from a popular auction site a couple of glass-plate holders that I thought were common 8x10 exterior dimension..but they were not, they are a little wider, thus won't fit into standard 8x10 view camera backs.

The locating ridge on them is in another place also, but since it is outside the place the ridge is on conventional film holders, I don't think that is much of a problem.

One holder says 8X10 STERLING PLATE..it is a double sided plate holder with one set of wood inserts for using smaller plates.

The other holder says 8x10 BROMIDE. Folmer Graflex corp. It is a single-side holder with a hinged back and also came with one set of reducing inserts made of wood. This would be harder to "cut down" because it has the hinges for the back wrapped around one end.

I had hoped one of these holders to form the basis of a wet-plate holder to use with my standard 8x10 cameras. I guess my options are to either carefully cut one of the holders down in height so it will slide in under the ground glass on an existing 8x10 camera, or find a 8x10 plate back that would fit these holders and I could adapt to one of my wood 8x10 or 11x14 field cameras. I am fairly good with adapting camera backs and lensboards.